This is my main cube, a 180-cards abomination.
It doesn't follow any overarching design principles, and has been designed almost entirely from the ground-up, by following what I liked about each iteration of the cube. It therefore mostly evolves after each play session, where I use feedback from the session to change and grow the cube.
I still strive to maintain a few design goals :

• Short, intense, interesting games
• Deep drafting experience
• Aggro, Midrange, Control AND Combo all viable

At the moment, the cube is undergoing an identity crisis : goodstuff midrange is too good, using reanimator tools inside an aggro/fair shell makes it very explosive, while the threats are really hard to interact with. The great mana fixing then allows you to splash most of these top tier cards and ignore all synergies.
I'm in the middle of restructuring the threats, replacing the most egregious mulldrifter with baneslayers, while improving the quality of interaction. This should let slower decks control the "explosive value" players, and lead to more interactive gameplay overall.